(1) Field of the Invention
The present invention relates to a synthetic jewel crystal. More particularly, the present invention relates to a chrysoberyl cat's-eye synthetic single crystal in which the physical characteristics and chatoyancy effect (cat's eye effect) of natural cat's-eye are reproduced.
(2) Description of the Prior Art
When light is incident in natural cat's-eye, a straight white bright line is caused to appear on the surface by the reflecting and refracting actions of inclusions in the crystal. The width of this white bright line is changed with the change of the illuminance of the incident light as in case of the pupil of an eye of a cat. Accordingly, cat's-eye is highly esteemed as a jewel.
The output of natural cat's-eye is very small. Accordingly, products obtained by embedding a foil of a metal such as aluminum in a matrix such as a synthetic resin or glass so that a straight white bright line is formed on the surface by the reflecting action of the metal foil have been provided as substitutes for natural cat's-eye.
In these substitutes, when light is incident, a straight white bright line is formed on the surface, but the change of the width of the white bright line (cat's-eye effect) with the change of the illuminance of the incident light is hardly caused. Moreover, since the hardness (Mohs hardness) of the glass or synthetic resin as the matrix is about 6 and the matrix is much softer than natural cat's-eye having a hardness (Mohs hardness) of 8.5, the surface is readily scratched or damaged and these substitutes cannot be regarded as being equivalent to natural cat's-eye in the physical characteristics and cat's eye effect.